Comment 1 for bug 1577768

I, too have the same issue. I tested with the Ubuntu Gnome DE as well - same issue. It appears to be DVD related, as I can replicate it on 3 different computers (1 Toshiba laptop, 1 no name Chinese laptop, and a Dell desktop) all with 16.04, by using the same DVDs.

Some DVDs mount OK others do not, but it is not an intermittent thing. If a DVD fails to mount once, it fails to mount always.

There is a small amount of posting in forums on this matter, so it affects more than one or two people.